Sheldon Coopers X-Ray Skulls Shirt

There's a small handful of Sheldon's shirts that, as interesting as they look, remain to be a perplexing mystery to most us on the internet. This is one of those shirts. While it's difficult to make out much from it, there appears to be x-ray humans skulls (well, at least one) and even what looks to be the x-ray skull of... a dinosaur? I dunno.

If anyone can shed light on what this intriguing shirt represents or, more especially, where we can get our hands on one, please let us know. The not knowing is torturous.

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